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• Milling some MDF

  Daniel Nikolajsen • 06/08/2021 at 12:07 • 0 comments

  Yup, aluminum was a bit too tough for my benchtop CNC. So I found a supplier of tooling board that I hope to try out soon, they promised to send me some samples. Tooling board is a high density polyurethane block that you can easily machine and hopefully use to make injection molds. 

  But, it is quite expensive.

  Thats why today, I tested out the CNC gcode with a piece of MDF wood board. It worked quite good in the beginning, but when I got to some depth the thinner details snapped right off. Hopefully tooling board wont have this issue, or I will need to replace all the smaller details with metal pins which would be very time consuming.

  But in total, I'm quite happy with the experiment. Slab some sealer on the mold and I can use it to try the injection molding machine. If it works and the entire mold gets filled up with plastic, I will know if I can use some sort of polymer molds instead of aluminum. If not, I probably need to spend a few thousand dollars on contracting someone to make the molds. 

• Plastic fantastic

  Daniel Nikolajsen • 06/06/2021 at 15:05 • 0 comments

  For the second attempt with the injection molding machine I went to our old farmhouse in the woods. No neighbors to disturb if the contraption starts bellowing out smoke like the last time.

  But it didnt! It actually worked quite good this time, even if some improvements are needed for it to be truly usable. All in all, not too bad for a machine that only cost me around 400 USD.

  It will probably suffice to insulate the nozzle, preheat the aluminium mold plus redesign it with a slightly bigger inlet. Because the melted plastic solidified way to quick and didnt get very far into the mold as you can see...

  And of course this is not one of the final molds, but just an early attempt at milling aluminium in my benchtop CNC.

  Slow but steady. Build, measure, learn! 

• Glorified smoke machine

  Daniel Nikolajsen • 06/03/2021 at 12:10 • 0 comments

  Today was the day I fired up the injection molding machine for the first time. Literally, "fired up". It worked like a charm the first few minutes, but then in an instant it smoldered nasty white smoke all over the apartment. Thank god for emergency stop buttons.

  After some guessing, I found out a few errors to fix. First I need to adjust the PID thermocontrollers to have a slower cycling of the heaters, plus relocate the thermocouplers ("sensors") closer to the actual heaters for a faster response.

  The main fault was that one thermocoupler was mounted directly to the nozzle block, which because of its size and mass heats up a lot slower than the actual barrel inside the heater element. Therefore the plastic closest to the heater probably goes up to over 250 degrees celsius (500 fahrenheit) before the nozzle even have reached 150. 

  Some insulation around the nozzle is also probably a good idea. 

  Plus, next time I will definitely bring the whole setup outside =) 

• Improvements to the app

  Daniel Nikolajsen • 06/03/2021 at 05:10 • 0 comments

  The list is long of all the todos, but yesterday I finally got the new app improvements working. Automatic kepler retrieval from Celestrak, with a search functionality. Now you always have the latest TLEs ("coordinates") in your app, plus you can easily swap between sats.

  But there's a lot more coming. I am making a world map that shows where the satellite is, plus a manual rotator control, plus automatic IP search, automatic GPS position retrieval, remove the need for restarts between sat changes etc etc etc

• Spring is in the... machine

  Daniel Nikolajsen • 05/28/2021 at 09:09 • 0 comments

  Today I built the last remaining part for the injection molding machine; a spring mount for the actual barrel that will contain the melted plastic. With this, you can put your mold a few millimeters under the nozzle and when pressure is applied from above, it gets pushed down against the mold, giving a decent seal. 

  But now its time for coffee to get some energy back. Unfortunately I experienced a nasty customer trolling and threatening me despite me being friendly, trying to solve the issue and even issued a refund. But thats the downside of doing business, sometimes you have to deal with some rotten eggs. Telling from some forum threads, its apparently not his first time making trouble. Thankfully the mails I get once a week or so from customers praising me for my great customer support and innovative product is what gets me up in the morning. Thank you, and keep em coming!

• One more day

  Daniel Nikolajsen • 05/27/2021 at 17:33 • 0 comments

  Yup, tomorrow is probably the day when I finish the injection molding machine. It's been a great run, but soon it is time to see if it will work as intended. At least the electronics are working now, with double thermostats and (at least for my small workshop) a massive hydraulic setup. *fingers crossed*

• First try at milling aluminium molds

  Daniel Nikolajsen • 05/25/2021 at 06:59 • 0 comments

  For the injection molding to work, I need to have molds. Yesterday I started with my first ever try at milling aluminum in my homebuilt CNC-machine. It started off quite okay, but then suddenly the z-axis dropped and buried its nose deep in the aluminium stock. The code and everything seems okay, so I am wondering if it was the stepper motor going crazy thanks to excessive heat. 

  Today I have put a heatsink and a fan on the motor, hopefully that will do the trick. Otherwise my next experiment will be to make molds in a somewhat softer material like polyurethane or polyester, because aluminium is both tricky, hard and expensive.

• Finished the instructions

  Daniel Nikolajsen • 05/21/2021 at 12:10 • 0 comments

  Today I got time to finish the assembly instructions, which required a lot of pictures. But now it's as good as it needs to be, for everyone to be able to put together their kit. And together with the video, I would be very surprised if anyone managed to mess up their build =)

  The full instructions can be found at www.satran.io/downloads

• Assembly instructions deluxe

  Daniel Nikolajsen • 05/11/2021 at 09:53 • 0 comments

  The assembly instructions for the satellite rotator has been sparse, since I made a video I assumed that would be enough. But it seems some prefer the printed version, so today I started a much more detailed manual with a photo for every step. Ingvar Kamprad would have been proud... (for those who arent Swedes, he's the founder of IKEA)

• Its all in the fine... parts

  Daniel Nikolajsen • 05/10/2021 at 08:58 • 0 comments

  Welding together the big frame for the injection molding machine was the easy part. Now comes all the small stuff that takes up all the time, but makes all the difference. Todays mission is to make holders for the temperature sensors which will give a good connection against the circular cylinder where all the melted plastic goes. It's the aluminium block you see in the lower right...

  Also the brass end plug needs to be transformed into a makeshift nozzle, which is why Im taking a trip later this week to my metal shop out in the woods. The nozzles need to be machined nicely and get a hole drilled through the middle in a perfectly sized diameter (that I have no clue about). I think I'll start with 3mm.

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